Hey Guys, I have the chance to score a 63 GMC long bed truck thats all og it has the 305 v6 in it. My ? is how good are these motors, I heard you can't rev them over 3700 rpm not to sure if this is true. Are parts still out there for a good price? Will a chevy 250 straight 6 bolt in there with out a lot of mods? Any advice will help its one hell of a deal but not sure on the motor and I would like to keep a 6 init of some sort Thanx For the help
I had a '60 1 ton stake bed GMC in the mid 70's. It had a 305 with a 4 speed hydramatic. Always ran you could not overload it & it got horrible gas mileage-even when it was empty.The engine was reliable, but sucked for gas mileage.
They did have lots of torque to them. I drove one in an old tow truck, never knew how bad the gas mileage was since when you haul junk cars, gas is free. (We'd get the gas out of the tank when they removed them at the 'yard, carried more than a few spare gas filters.). I've seen them hotrodded here in the past, too much like work though. Bob
A former employee had a GMC with the big Vee Six, standard trans truck. He and his brother cleaned it up, painted it copper and put a set of stock wheels and approximate sized stock tires. Drove like an old truck. He installed a set of Bilstein shocks front and back and installed an S-10 T5 trans, it transformed that truck into a very nice daily driver. 15-18 MPG and could run along at 75-80MPH without issues. Those 305 V6s may not get you there in a hurry, but they will run very smooth and last a long freaking time.
The one I knew was old... but quiet and ran smooth, had the big clutch and the tow truck 4-speed and something like 5.38 gears. It topped out at 50... Bob
A boat anchor, no damn good in a truck, gutless and thirsty. Other than that, it's OK, I guess...........
They make good tow truck motors, if you keep it be sure and watch the oil pressure, if or when the fuel pumps fails it will foul your oil with gas. The 250 is an easy swap if you must won a six cylinder.
The swap....you need to change the motor mount brackets on the frame, get the right brackets for the engine, get the right bellhousing, figure out if you're going to go with a mechanical or hydraulic clutch (63 gmc used hydraulic, 63 chevy was mechanical). It's pretty straightforward except for that.
The GMC V6 is quite different from a Chevy engine. Nothing that that bolts to the 305 will fit a Chevy six.
I was picking up some scrap blocks at a truck shop one day years ago... I asked them what this odd 6-banger came out of.. GMC truck! The block itself was a nut buster. Bob
Thanx for the help guys I think i'm going to get rid of the v6 and go with a straight. Do Chevy straight 6's have two side motor mounts and a front or just to side ones? I've heard both but have never built or worked on one. Well I hope I can talk my wife in to letting me buy this truck, I'll keep you guys posted if I'm lucky I'll have some pics soon. Thanx againg for the info on the v6
63 was the first year of the "new" six engine. It uses side mounts and has the same bellhousing bolt pattern as the V8 engines. So, as long as you have the truck engine mount brackets (go between the engine and the mounts) you can swap it in just as if it were a V8. If you are going to use an automatic transmission, you'd want to get a transmission rear crossmember from a 64-72 truck that came with an automatic. If you are using a manual trans, you could use the later truck or car setup with the automatic type rear crossmember, or you could use the 55-59/63-72 truck crossmember. The 60-62 chevy and 60-63 GMC trucks were oddballs, they had a hydraulic clutch. I'm pretty sure you can swap the 63-66 chevy mechanical clutch linkage into the truck, in fact I was thinking about doing that with a 63 GMC I had a while ago, it looked like all the parts I had from a 66 chevy truck would fit it just fine.
Squirrel, For reference only a piece of 2x3 box tubing bolted directly to the lower flange make a perfect cross member for a tail shaft mount on an automatic.
Well I guess not perfect because it is not original. Most of the tie when I don't have an original pieces and don't know exactly where to find one I go to the scrap pile.
I'm screwed, I sold off my scrap pile for scrap. I got rich, but now I don't have anything to build cars with.
Or you have the resources to find the correct pieces instead of going to the scrap pile. Always two side two the coin I suppose.
The straight six I tring to get is out of a 69 chevy c10 and I do want to run an automatic, I was thinking a 700R4 it would be nice to have overdrive. What do you guys think.
My .02 on the V-6, having been around them for several years, one in a two ton truck we still have and one in a 64 long bed we traded off in "72", they're not a speed demon, they will haul the load, and the 2 ton gets 10 to 12 mpg loaded one way, back empty, this one runs the 2 barrel Stromberg carb If I remember correctly, there are after market parts for them but I doubt performance comes up much, the 6066 GMC page has a lot of info on these monsters, if your not in a big hurry there wouldn't be anything wrong with one as a daily driver, thats what they were in their day, AND you don't hear those very often anymore with the right muffs they sound pretty good.
That would probably work. You'll have fun getting the TV cable set up, make sure you do it right so the transmission is working properly. They fry if it's not right.
Wish you were closer bro, I am taking a good running 25o six out my 66 c-10. It could be had for $200.00, but lottsa miles between us. Good luck on your project. ~sololobo~
Throttle Valve. It's the cable that connects the transmission valve body, to the engine throttle. So the transmission can adjust how it works, according to how much power the engine is making. If the throttle is barely open, it shifts softly and early, and if the throttle is wide open it shifts hard and late. If you have the the TV cable set up wrong and the transmission thinks the throttle is not open as far as it really is, the clutches don't get much apply pressure, and they can't hold the torque, and burn up. The TV cable takes the place of the vacuum line and vacuum modulator. I prefer older transmissions with the vacuum system.
If you make the switch, while you are at it change out the front springs to, or the nose will ride high and the ride will be rough, those big V-6's where very heavy.
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